Believe it or not, Marta, there are some conscientious boat owners who do voluntarily use pumpout waste disposal because they care about a cleaner ocean. If you want to believe that your stuff doesn't stick and it just magically disappears or get washed down current then that's your perogative. But it causes problem whereever it goes. It's possible that the currents mostly swirl around and around spreading the bacteria and trawling, storms and upwellings stirs it up even more. Sure we should try and identify and eliminate the sources of bacterial runoff but human waste from boats we know is a problem that should be dealt with. Don't you want cleaner water to swim in? Healthier seafood to eat? Healthier and more reproductive fish stocks?